This volume is concerned with the philosophical foundations of Psychical Research. Traditional metaphysical theories have led to apparently insoluble problems concerning the nature of mind, of matter and the relation between the two. The author holds that these theories arise from misconception about the way in which words acquire meaning. His aim is to show that once the relation between words and the experienceable entities which they mean is clearly understood, these seemingly insoluble problems disappear, and the metaphysical theories which give rise to them are seen to be literally...